End extensions of models of linearly bounded arithmetic Original Research Article

We show that every model of IΔ0 has an end extension to a model of a theory (extending Bussʹ S20) where log-space computable function are formalizable. We also show the existence of an isomorphism between models of IΔ0 and models of linear arithmetic LA (i.e., second-order Presburger arithmetic with finite comprehension for bounded formulas).